Biomedical subjects
Publications and source records attributed to F Vianello.
A novel method for isolation of amine oxidase from bovine plasma is reported; it involves a two-step procedure, namely ammonium sulfate fractionation and affinity chromatography with elution by aniline, which is a competitive inhibitor of the enzyme. A homogeneous enzyme, characterized by a specific activity of 0.44 U/mg, was obtained with a yield higher than 50%.
Two protein kinases active on casein and phosvitin were partially purified from the soluble fraction of ejaculated bovine spermatozoa. They were operationally termed casein kinase A and B based on the order of their elution from a phosphocellulose column. CK-A showed an approximate molecular mass of 38 kDa, and it phosphorylated serine residues of casein and phosvitin utilizing ATP as a phosphate donor (Km 19 microM). Enzyme activity was maximal in the presence of 10 mM MgCl2, whereas it decreased in the presence of spermine, polylysine, quercetin, and NaCl (20-250 mM). CK-B seemed to have a monomeric structure of about 41 kDa; it underwent autophosphorylation and cross-reacted with polyclonal antibodies raised against recombinant alpha, but not beta, subunit of human type 2 casein kinase. It phosphorylated both serine and threonine residues of casein and phosvitin, utilizing ATP (Km 12 microM) but not GTP as a phosphate donor. Threonine was more affected in the phosphorylated phosvitin than in the partially dephosphorylated substrate. CK-B was active toward the synthetic peptide Ser-(Glu)5 and calmodulin (in the latter case, in the presence of polylysine), and it was activated by spermine, polylysine, MgCl2 (30 mM), and NaCl (20-400 mM). The activity of the enzymes was not affected by cAMP, or the heat-stable inhibitor of the cAMP-dependent protein kinase, or calcium.
BPH is a very diffuse condition among males increasing in incidence with the age. This explains the large interest in the evaluation of the different strategies concerning BPH treatment. The gold standard has still to be considered the transurethral resection of the prostate which all the other treatments must be compared to. More recently as alternatives to the invasive therapy, so called minimally invasive treatments have been proposed (thermotherapy, prostate dilatation, intraprostatic stents) whose real significance is not completely evaluable yet. As far as medical treatment is concerned, phyto-therapeutic agents have been partially replaced by different substances (alfa- blockers; 5-alfa reductase blockers) that are expected to have a promising future.
DNA nuclear ploidy determined by flow cytometry was evaluated from prostate tissue in 51 patients with prostatic cancer who had undergone radical prostatectomy. DNA ploidy pattern was diploid in 46% and aneuploid in 54% of tumors. DNA ploidy was compared to histological tumor grading. 92 Aneuploidy was found in 0% of the tumors with Gleason score between 2 and 4 in 62% between 5 and 7 and in 50% between 8 and 10. Our results suggest there is no relationship between the two parameters.
UNLABELLED: A substantial number of duodenal ulcer (DU) patients relapse despite maintenance treatment with antisecretory drugs. The influence of certain risk factors and the heterogeneity of the disease could explain such behavior. The present prospective, open study compares the one-year clinical outcome (with upper GI endoscopy at the beginning of the study, at 6 and 12 months, and at every symptomatic relapse) of four groups of DU subjects, consecutively recruited from December 1987 to December 1988, separated in accordance with whether or not a bleeding DU episode had previously occurred, and whether or not an evaluation of gastric acid secretion had been made. Thus, Group I (17 patients; 12 males, 5 females) included heavy smokers and/or gastric acid hypersecretors; Group II (13 patients; 12 males, 1 female) non- or light smokers non-hypersecretors; Group III (34 patients; 22 males, 12 females) subjects with unknown gastric acid secretion; Group IV (33 patients; 30 males, 3 females) previously bleeding DU patients. All patients, except those in Group II (who were left untreated), were given ranitidine 150 mg at bedtime. The outcome of Groups I+II was compared with that of Group III (considered as "standard therapy") and Group IV patients, the latter presumably with a low risk of relapse because of the low prevalence of smokers. STATISTICS: Chi-square test, Fisher's exact test, analysis of variance and the logrank test. During the year of follow-up, 27/97 patients withdrew from the study, while 18 had a DU relapse (remission rates 82.1% +/- 7.4% in Groups I+II, 70.5% +/- 8.4% in Group III, 87.5% +/- 5.9% in Group IV).(ABSTRACT TRUNCATED AT 250 WORDS)
Mucosal blood flow performs an extremely important role in microcirculation wherein alterations necessarily lead to severe gastric and duodenal mucosal lesions. The removal of back-diffused H+ ions through the adaptation of microcirculatory flow represents a valid defence mechanism. The blood flow's inability to contain H+ back-diffusion lies at the bottom of rapid-onset acute mucosal lesions; moreover, it probably contributes to the onset of chronic ulcer in certain areas already precariously supplied, because of the breakdown of the mucosal barrier or a further reduction in blood supply. Portal hypertension leads to altered blood flow in the gastric microcirculation. This haemo-dynamic condition brings about a series of endoscopically evident changes which are probably a consequence of the conspicuous increase in mucosal and submucosal vascular area. This haemodynamic situation may be an aetiopatho-genetic factor in the cirrhotic subject's marked sensitivity to gastric mucosal damage.
With a view to describing the natural history of duodenal ulcer, currently linked with powerful and widely used drugs, we retrospectively reviewed all patients followed-up at our unit between 1978 and 1989. All DU subjects with at least 5 years of clinical-endoscopic follow-up were admitted to the study. Concomitant gastric ulcer, previous gastrointestinal surgery and treatment other than with H2-blockers (where necessary) were considered exclusion criteria. Forty-four patients (35 males, 9 females, mean age 44.5) proved eligible for this study. At monthly intervals in the patients' history of ulcer disease (starting from a baseline month 0 when ulcer symptoms first appeared), we compared all cases in which the duration of disease coincided, i.e. for each month of the clinical course of the ulcer there was a certain number of patients at the same point in time; patients' histories coincided variously over a period ranging from 0 to 15 years. We considered endoscopically-diagnosed relapses (both symptomatic and asymptomatic) and hemorrhages as marker events for the activity of DU disease. A year-by-year duodenal ulcer activity rate was obtained for both treated and untreated subjects, as follows: No. of events/mean No. of patients followed-up per month x 100. Fisher's exact test and multivariate analysis (stepwise logistic regression) were used to investigate risk factors of poor outcome. We found that the years between the 1st and 5th and between the 10th and 15th from the onset of duodenal ulcer disease had higher peaks of activity, mostly in untreated subjects.(ABSTRACT TRUNCATED AT 250 WORDS)
F- added to an erythrocyte suspension shows two separated resonances arisen from intra and extracellular compartments. Cu, Zn superoxide dismutase dominates the longitudinal relaxation rate of the intracellular F- resonance, while diamagnetic interactions with hemoglobin contribute mainly to the transversal relaxation rate.
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No definite relationship can be demonstrated between benign prostatic hyperplasia (BPH) and prostatic cancer on the basis of various anatomic and morphologic features. However, interesting recent observations suggest a link between BPH and prostate cancer. Clinically, the simultaneous presence of benign and malignant disease is observed quite often, and this coexistence is bound to increase with the age of patients. Possible intermediate forms between BPH and early cancer have been investigated. Two premalignant lesions have been identified: atypical adenomatous hyperplasia and prostatic intraepithelial neoplasia.
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A different pathophysiological mechanism is widely accepted for gastric and duodenal ulcer. In particular, the exact role of gastrin in the determinism of non hormono-dependent peptic ulcer disease is not completely clarified. Therefore, the aim of present study was to analyse fasting and post-prandial serum gastrin levels in 99 duodenal ulcer patients, 17 gastric ulcer patients and 11 subjects presenting an association of gastric and duodenal ulcer. The possible correlation between post-prandial gastrin concentrations and basal and maximal acid output in the 3 fasting serum gastrin levels appear not different among the 3 classes of patients, while post-prandial gastrin concentrations are statistically higher at 15 minutes in duodenal ulcer patients and in subjects with the association of gastric and duodenal ulcer as compared to gastric ulcer patients. Mean fasting and stimulated gastrin levels are higher in gastric ulcer females than in males during the entire test and with statistically difference at 30 minutes. The concentrations of the hormone are not different in males of the 3 groups of patients at basal time, while are statistically lower at 15 and 30 minutes in gastric ulcer males compared to the males with duodenal ulcer and the association of the localization. Finally, positive correlation has been observed between BAO and MAO and post-prandial gastric concentrations in the 3 groups of patients, while there is an inverse correlation between the previous parameters as regards sex, both in gastric and duodenal ulcer.
Helicobacter pylori (H.p.), has been shown, experimentally, to exert a proteolytic activity against mucous fractions. Aim of this study was to assess the prevalence of H.p. in peptic ulcer and to analyze its possible influence on gastric mucus components, on peptic activity in gastric juice and the possible action on peptic secretion. 223 patients undergoing upper gastrointestinal endoscopy were analyzed for the presence of H.p. in the mucosa: 99 duodenal ulcer patients (D.U.), 58 gastric ulcer patients (D.U.) and 66 dyspeptic subjects. In each patients, three contiguous gastric biopsies were taken at the antrum: the first was evaluated for gastritis (Whitehead Criteria), the two other analyzed for H.p. with a rapid urease test. In a subgroup of 25 D.U. and 18 G.U. patients, two other biopsies were taken at the fundus corpus of the stomach, to evaluate peptic secretion. To determinate mucous components (acid and neutral glycoproteins, galactose and N-acetylneuraminic acid), gastric juice samples were collected during endoscopy. H.p. was present in 89% of antral biopsies in D.U., in 56% of G.U. and in 51% of D., and was associated to antral gastritis. As regard gastric juice components, we observed an increase and a decrease of acid glycoproteins, respectively, in D.U. and G.U. patients with H.p. infection. An increase of peptic activity has been found in the gastric juice of both gastric and duodenal ulcer patients H.p. positive (G.U. p less than 0.05). On the contrary, no significant differences were observed on peptic activity in the fundus-corpus biopsies between H.p. positive and H.p. negative patients.(ABSTRACT TRUNCATED AT 250 WORDS)
A technique for determining pepsinogen group I (PGI) concentrations in endoscopic gastroduodenal biopsies is described and validated. This method has a good precision (intra-assay CVs 4.1% to 8.4%; between-assay CVs 4.6% to 9.3%), and analytical recovery is satisfactory (94% to 102%). Results were uninfluenced by the storage interval of the samples. At PGI-producing sites (i.e., fundus, corpus) peptic activity was greater than in the antrum and duodenum. PGI concentrations in serum and in gastroduodenal biopsies were not correlated. This simple, reliable method can quantify better than other assays peptic activity in humans, without being influenced by gastric secretory volumes. It will also facilitate prospective studies on the effect of various secretagogues in vivo and evaluations of the influence of anti-ulcer drugs on peptic secretion.
Conflicting data are present in the literature on pathophysiological role of serum gastrin and peptic ulcer disease. The aim of this study was to evaluate, in duodenal ulcer patients, the possible correlation between post-prandial serum gastrin concentrations and some epidemiological (sex, family history, onset of the disease, blood group status, smoking habit, alcohol consumption) and clinical (effectiveness of therapy, bleeding episodes) factors. The gastrin levels were expressed in absolute values and as per cent increase of fasting serum gastrin concentrations. As regards sex, the per cent increase of fasting serum gastrin concentration was significantly higher in females (No. 16) than in males (No. 60) at 30 and 60 minutes (192.25% vs 116.52% and 105.42% vs 40.96% respectively; p less than 0.05 and p less than 0.005). Post-prandial serum gastrin concentrations, expressed as per cent increase, were higher in heavy drinkers (No. 14) and statistically significant at 120 minutes (40.57% vs 9.58%, p less than 0.025); as well as in smoker patients (No. 31), at 15, 30 and 60 minutes (227.59% vs 123.52%, 177.23% vs 101.62%, 0.025 and p less than 0.05). Post-prandial gastrin was unrelated to blood group status, onset of the disease, family history, effectiveness of medical treatment and bleeding episodes.